Certain endocrinological disorders are currently diagnosed via traditional in vitro diagnostic tests that employ sandwich immunoassays in an effort to achieve the desired selectivity and sensitivity for the hormone of interest. However, the peripheral metabolism of whole hormone into fragments and the relative clearance of whole hormone and hormone fragments vary widely from person to person and create a complex mixture to be measured. Depending on the diagnostic test that is chosen (and the corresponding recognition elements of that test), there can be significantly different test results for the desired protein of interest, using the same calibration standards. In addition, a better understanding of the relative populations of a protein and its fragments and the underlying kinetics of metabolism of the protein can potentially provide important information for more effective understanding and treatment of particular endocrinological disorders—particularly in surgical operations. Unfortunately, the kinetics of hormonal secretion, metabolism, and clearance cannot be well understood with diagnostics that evaluate only a single form of the protein.
By way of example, approximately 100,000 patients undergo parathyroidectomy each year to treat primary hyperparathyroidism. Intraoperative measurement of intact parathyroid hormone (“IOPTH”) is a critical step in the operative management of patients undergoing surgery for hyperparathyroidism because it is used to monitor the blood concentration of intact parathyroid hormone (PTH) and to confirm that the offending parathyroid gland has been removed. Measurement of Intraoperative PTH (IOPTH) reduces rates of full neck exploration as well as rates of re-operation to remove residual parathyroid tissue, resulting in decreased risk and morbidity to the patient. In many institutions, IOPTH measurements are routinely performed by sending patient specimens to a central lab which are then analyzed. Some institutions, such as The University of North Carolina at Chapel Hill (UNC), perform IOPTH measurements near or within the operating room (OR) suite, which has been shown to reduce specimen turnaround time and procedure costs. But, a low-cost and portable PTH assay could further reduce IOPTH costs and help broaden the adoption of performing IOPTH measurements within the OR suite.
The presently disclosed subject matter addresses the above-mentioned needs and other needs in the art.